London: A tiny microchip implanted in the back of the eye has been found to restore sight, researchers said.

The bionic eye was tested on a group of blind persons, with encouraging results.

One man saw his girlfriend`s smile for the first time, while another was able to read his own name. It is thought the device could even work in certain cases of blindness existing from birth.

The results have been described as `quite astonishing` by eye surgeons, and the first Britons could be benefiting within months, reports the Daily Mail.

Experts say the sub-retinal implant could revolutionise the treatment of blindness in the same way as cochlear implants have transformed the life of the deaf, according to the journal Proceedings of the Royal Society.

First to benefit will be people with retinitis pigmentosa, a hereditary disease that gradually destroys the light-sensitive retina at the back of the eye, leading to total blindness.

But in time, the bionic eye could also be used to treat age-related macular degeneration, the most common cause of blindness in the elderly, which is currently incurable.

Robert MacLaren, an Oxford University professor of ophthalmology, said: "Now when I discuss eye disease with patients, I can, at least in some cases, hold out some hope.

"For a patient, it will make it easier to deal with the somewhat appalling prognosis that they are going to lose their sight," he said.

The device, the brainchild of German firm Retina Implant AG, consists of a very thin microchip, just 3mm in length, packed with 1,500 light sensors designed to replace those in the human retina.

Although bionic eyes have been piloted before, this battery-powered implant is the first not to require cumbersome accessories such as a camera mounted on dark glasses.